Electronic data interchange (EDI) is the structured transmission of data between organizations by electronic means. EDI can be formally defined as the transfer of structured data, by agreed message standards, from one computer system to another without human intervention. It is used to transfer electronic documents or business data from one computer system to another computer system, i.e. from one trading partner to another trading partner. It is more than mere e-mail; for instance, organizations might replace purchase orders and invoices with appropriate EDI messages. EDI also refers specifically to a family of standards that are strictly adhered to and updated.
In 1996, the National Institute of Standards and Technology defined electronic data interchange as "the computer-to-computer" interchange of strictly formatted messages that represent documents other than monetary instruments. EDI is the transferring of messages between two parties, either of whom may serve as sender or receiver. The formatted data representing the documents may be transmitted from originator to recipient via telecommunications or physically transported on electronic storage media. In EDI, the usual processing of received messages is by computer only. Human intervention in the processing of received messages is typically intended only for error conditions, for quality review, and for special situations.